Where did I go wrong in this rook endgame?

Optimissed

The way you want to play it, white has the more active rook and black's rook can be harrassed by white's K. It's much harder for black to get his king into it. With black's R on b7, it doesn't have a lot of squares but it defends black's pawn base and black is always threatening to push the b pawn. Ultimately, black wins because his K zigs across to attack white's R and then zags back to eat his pawns. Easy forced win. Even I could do it.

tlay80

Optimized, the point is that there are lots of positions where you'd *love* to have your rook behind the pawn, but it's not in the cards.  This one, assuming you look past the nice catch on move 31, is one of them.  And there are lots more where there never was a chance to begin with.

I recently worked through (part of) the thirty pages Dvoretsky devotes to this sort of an endgame.  Short answer is that it's right that the best chances usually involve stopping at the 6th rank and walking the king over.  In this case, it also helps that it's a knight's pawn and not a rook pawn.  That's because White has to prepare to eventually give up their rook for the advanced pawn. But meanwhile, they'll have won some or all of your kingside pawns, so your king has to get back in time to win a rook vs two-or-three pawns endgame. This would be harder if it were one file further away, but on the knight's file, it's often a win -- at least in practice.  Theory, amazingly, still isn't completely settled on some of these, and people are still finding improbable wins in allegedly drawn endgames and vice versa.  For instance, a drawing defense was apparently recently found to some endgames like this that involved White using their king to block Black's king from getting to b2.

llamonade2

@optimissed
Oh, with white's structure I guess you're right.

In general it's not enough to win though. At least from what I remember. For example put the pawn on g2. White will have to be accurate though.

I still say the best winning chances were a lot earlier (although I haven't put any of this into an engine yet). But yeah, with the rook behind and white's damaged structure, it shouldn't be too hard to win.

drmrboss
llamonade2 wrote:

That position is a pretty well known book draw. The engine eval means nothing in endgames like this. It needs to be showing at least +2 for you (sometimes a lot more) for it to be winnable.

No,

 

This position looks easy win for black.

My plan is 

1. b5 ( without b5, rook have to go Rc6, Rf6 that will block movement of king)

2. Rc5

3. Rf5.

Everything is completely stable.

Just march the king with the pawn and when pawn reach to b7, bring your rook to "a" file or "c" file to protect your king from opponent rook check.

 

. If white king approach to pawn, white will lose all pawns.

 

I can run my stockfish  for approval if people disagreed with me. wink.png

llamonade2

I meant later it was a basic book draw.

Also you guys rushing to your engines for the answer miss the basic idea that the extra pawn by itself is not enough to win even on move 32. Black needs the help of white's poor structure and slightly worse pieces.

Optimissed

I was never great at endings, except sometimes. I'm improving but it's taken 33 years, near enough, of competitive chess.

Optimissed

At one time I needed to be three pawns up to win a game against a good endgame player.

Optimissed

btw I understand what you were doing earlier. I appreciate it.

llamonade2

Sometimes I have fun and come off as a bigger jerk than I really am, so I'm glad you didn't take it too badly happy.png

Optimissed

Thought you were drunk. Then realised it was an act of friendship.

NotYourAveragePlayer
tlay80 wrote:

Optimized, the point is that there are lots of positions where you'd *love* to have your rook behind the pawn, but it's not in the cards.  This one, assuming you look past the nice catch on move 31, is one of them.  And there are lots more where there never was a chance to begin with.

I recently worked through (part of) the thirty pages Dvoretsky devotes to this sort of an endgame.  Short answer is that it's right that the best chances usually involve stopping at the 6th rank and walking the king over.  In this case, it also helps that it's a knight's pawn and not a rook pawn.  That's because White has to prepare to eventually give up their rook for the advanced pawn. But meanwhile, they'll have won some or all of your kingside pawns, so your king has to get back in time to win a rook vs two-or-three pawns endgame. This would be harder if it were one file further away, but on the knight's file, it's often a win -- at least in practice.  Theory, amazingly, still isn't completely settled on some of these, and people are still finding improbable wins in allegedly drawn endgames and vice versa.  For instance, a drawing defense was apparently recently found to some endgames like this that involved White using their king to block Black's king from getting to b2.

 

Which chapter or pages is it in Dvoretsky's endgame manual? I will have a look and see if it helps me understand how to play these kinds of positions.

NotYourAveragePlayer
llamonade2 wrote:
Lonteon wrote:

Trapping your own rook IN FRONT OF the pawn seems like a weird decision. I'd defend it from the side to get more rook mobility.

This makes sense, but when the pawn is so far back it means your rook will be on your 3rd rank, and actually it would be pretty easy for white to draw in that case too.

 

What exactly is the reason one would want to defend the pawn from the side and what is meant by "more rook mobility"? In effect, what are the concrete advantages of defending the pawn from the side?

NotYourAveragePlayer
llamonade2 wrote:

Putting it in front gives the best winning chances, and a rook in front of a knight pawn on your 6th can be technically challenging to defend (although I've forgotten the details). The basic reason is that it's closer to your king than, say, a rook pawn on the 6th.

 

So, am I understanding you correctly in saying that, generally speaking, with a black pawn on b3 the rook is better placed on b1 than a rook on b7? Why is that exactly? One hears all the time that rooks belong behind the pawns in rook endgames.

tlay80

It’s the section in Chapter 9 titled “Balance on one wing and an extra pawn on another.” Most relevant here is the subsection on knight pawns, though the two sections before it help set it up. Of course, white’s mangled pawn structure means it’s not exact. 

NotYourAveragePlayer

Thank you tlay80, I will definately have a look at that chapter!

llamonade2
Optimissed wrote:

Thought you were drunk. Then realised it was an act of friendship.

Maybe a little of both wink.png